Method of repairing scored cylinders



R. D. HEACOX. METHOD OF BEPMRING SCURED CYLINDERS. APPLICATION FILED MAR-18. 1921.

1,385,334. Patented Jui 19,1921.

.3035}. Hum? INVENTOR.

I BY UNITED STATES PATENT OFFICE.

METHOD OF REPAIRING SCORED CYLINDERS.

Specification of Letters Patent.

Patented July 19, 1921.

Application filed March 18, 1921. Serial No. 458,502.

To all whom itmag concern:

Be it known that I, Ross D. HEAOOX, a citizen of the United States, residing at Washington, in the-District of Columbia, have invented certain new and useful Imrovements in Methods of Repairing Scored ylinders; and I do hereby declare the followin to be a full, clear, and exact description 0% the invention, such as will enable others, skilled in the artto which 1t appertalns v to make and use the same.

This invention relates to a method for repairing scored metal objects. l

The mainobject of the inventlon 1s to provide a method by which scored engine cylinders may be simply, efficiently and economically repaired without the necessity for regrinding; which process will resultfm a practical and substantially permanent remlhe invention consists in the novel steps, processes, methods and materials hereinafter more particularly described and clalmed.

One sheet of drawings accompanies this specification as part thereof, in which llke reference characters indicate similar parts throughout.

The figures are all fragmentary transverse sections of an engine cylinder.

Figure 1 illustrates the cylinder with two narrow scores; 4

Fig. 2 illustrates the scores of Fig. 1 after they have been preliminarily cleaned out and prepared and filled with an alloy metal preliminary to scraping;

Fig. 3 shows the cylinder of Fig. 1 after the process has been completed and the surplus alloy metal has been scraped off to the true contour of the cylinder;

Fig. 4 illustrates a broad, shallow score; Fig. 5 illustrates a broad, shallow score cleaned out and double dove-tailed and filled with an alloy metal, and

Fig. 6 shows the final step with the broad score filled and finished.

It is a common occurrence in the use of explosive engines for the wrist pins to break or .work loose so as to come in contact with and score the cylinder wall. Such scores may be eliminated if the cylinder wall is suiticiently thick by regrinding the cylinder, but this necessarily weakens the cylinder throughout, requires expensive machinery and the removal of the engine.

In accordance with the present invention the scores in the cylinder are first cleaned out with suitable scraping tools until they have smooth bottoms 4 and undercut or dovetailed sldes 3-3, as illustrated in Fig. 2. ThlS is ordinarily sufficient in the case of narrow scores such as Fig. 2, but where the scores are broad as 2, it is desirable to further deepen the score centrally and provlde a further lower bottom 4 and supplementary undercut sides 3, making a further dove-tailed seat in the middle of the score as illustrated in Fig. 5.

When the scores have been thus cleaned out and shaped, a suitable flux such as kllled spirits or muriate of zinc is applied and the surface is tinned over throughout with the alloy or solder with which the score is to be filled. The score is then completely filled with a hard solder which has the characteristic of expanding upon solidifying. Antimony in suitable proportions is known to produce this effect in alloy solders and it may begenerally stated that any hard solder havmg thls quality is adaptable for use in this process. One formula for such a solder, which experiments indicate is particularly suitable, consists of 50 per cent. tin, 30 per cent. lead, 15 per cent. antimony and 5 per cent. copper. This alloy has a melting point between 450480 F. I

The scores are well filled with this solder so that its upper surface extends slightly above the normal surface of the cylinder. A scraper gaged accurately to the contour of the cylinder is then used to remove the surplus alloy metal and bring its surface to the true contour of the cylinder. An adjustable scraper peculiarly adapted to this operation is described in my co-pending application, Serial No. 452,868, Mar. 16, 1921.

It will be noted that in addition to the gri ping surfaces provided by the undercut wa ls of the scores described above, the alloy metal will be further secured to the cylinder wall by reason of the natural porosity of the cast iron. Experiments indlcate that the highly fluid molten alloy metal penetrates 'the pores of. the iron and by reason of its quallty of expanding in cooling grasps the iron and roots the insert to its place.

Having thus fully described my invention, I claim: 7

1. A process of repairing scored cylinders which consists in cleaning and fiuxing the scores and then soldering therein a hard solder having the property of expanding on cooling.

2. The process qf repairing scored cylinfilling said seat with a solder having the ders \which consists in cleaning and fiuxing property of expanding on coolin and scrap the score and soldering therein a hard solder mg the surplus solder away to the true con- 10 comprising tin, lead, antimony and cop er. tour of the cylinder wall.

5 3. The process of repairing scored cyiiin- In testimony whereof I afiix my signature.

ders which consists in scraping out the score to provide a seat having undercut side walls, ROSS D. HEACOX. 

